Hi there,
Have an excellent solution for you, high quality and secure, which can be modified to meet any needs you may have. Full details and an online demo can be found at:
"envrin" [dotcom] /exchange
Please take a look at the above URL, and let me know if you're interested. Things like functionality and theme change are no problem. Just let me know what you need, and consider it done, as your imgaination is the only limit. Ready to get started asap if you wanted.
Thanks,
Matt